Lighting fixture



G. ARRAS LIGHTING FIXTURE Dec. 19, 1933.

Filed April 29, 1931 fizz/@7227 Geo/ye drrcw, 45 M WM a? Patented Dec. 19, 1933 UNITED. STATES PATENT. .QFFICE I LIGHTING FIXTURE n 7 George Arras, Chicago, Ill. Application April 29, 1931. seams. 533,743" l 8 Claims. (ol. 240-78) This invention relates in general to an electric lighting fixture and has more particular reference to a fixture for excluding gases and for preventing condensation within the fixture parts. A principal object of the invention is in the provision of a lighting fixture which is sealed against the admission or escape of gases or Vaporswhich may be inflammable or dangerous, or may tend to condense, due to the heat of a m larnp within the fixture.

A further object of the invention is in the pro"- vision of a liquid seal for a lighting fixture, either at the joint ofthe globe or reflector, or at the mounting of the fixture support.

T1 A further object of the invention is in the provision of a sealed lighting fixture to prevent the admission of dirt, thereby keeping the globe clean for-a longer time and making frequent cleaning unnecessary.

companying drawing illustrating bodiments of the invention. i i p In the drawing: Figure 1 is a sectional view of a fixture c011 "structed in accordance with the principles of this invention and Figures 2 and 3 are sectional details modifications of the liquid seal. H In many places where electric lamps are used it is found that the heat of the lamp will cause a movement of gas or vapor to and from an enpreferred em:

showing closing globe, due to the expansion and con-V traction caused by the lamp when it is hot and cold. In some cases the vapor may condense l and collect in the fixture parts, as at the bottom of an enclosing 'globeor reflector, which may be objectionable if not actually dangerous.

It is also found that this action may occur in the pipes or conduits leading to the fixture, and to provide a seal fixture, it is necessary also to seal the passage from the supporting conduit pipe. The present invention proposes to overcome both of these objections by providing a sealing compound or liquid at the juncture of the 5 enclosing globe and at the socket support for the lamp itself In carrying out this invention, the fixture comprises a holder 5 having a threaded connection at its top with a conduit 6 and having exterior fins 7 for heat radiation. At the bottom of the holder is an external flange 8 for attaching a refiector 9 thereto by screws 10 orany other suitable fastening means and within the flange is a circular rib 11 which projects downwardly pro- Other objects will appear hereinafter, the ac viding a space between it ceivin' a fixture bowl or g The fixture globe'12 ha inner end of the holder However, this threaded to the passage of gases o and the flange lobe 12;

for res an external threaded portion 13 at its upper edge adapted to engage with a correspondingly threaded portion on the inner side of the reflector flange: 8 and at the recess isa gasket 14.

end gasket, connection does not ordinarily produce a joint impervious.

r, vaporsand the globe 12 is therefore provided with an inner flange 15 which extends inside of the rib l1 and below the lower groove 16 for receiving a extremity thereof forming. a circular,

sealing liquid or comlower edge of the rib 11.

Within theholder 5are projections 20 for reoeivi'ngsocket fastening screws 21, and surrounding the wire admission opening of the holder is a depending rib 22.

A lamp socket 23 is sup- 7 ported .by the screws 21 and an electric lamp'24 threaded into the socket in awell known manner with conductors 25 extending therefrom into the conduit 6.

In order to seal the opening into the conduit and to connect the conductors 25, a liquid sealing "cup 26 is interposed between the socket 23 and the projections 20 which is held. in place by the fastening screws 21 and this'lcup has an upward flange 27 which extends below the lower edge of the depending rib 22 so that a sealing liquid or compound 28 placed in the cup will extend upwardly above the lower edge of the rib 22 but will leave a space below the lower edge of the rib and the bottom stringing the conductors of the cup for loosely 25 through the sealing Instead of forming the ture asshown by Figure 2 prising a holder 31 with a ed on the outside and a may be employed comlower flange 32 threadglobe 38 with an offset upper rim 34 having a lower threaded rim'pore tion 35, the two threaded rim portions 32 and 35 being joined by a correspondingly threaded metal rim 36 which engages gaskets 37 and 38 at the top andbottom respectively. The reduced rim portion 34 of the globe forms a recess be-. Y

tween it and'the depend containing a sealing 39.

ing rim portion 32for p A somewhat similar modification is shown in Figure 3, in which the holder 40 has a lower rim 8 and rib 11 similar to that shown in Figure 1 and the globe has a single reduced rib 34 as shown in Figure 2, the joint being closed by a metal rim jectionable gas, vapor or dirt either from the interior of the room or. through the wiring conduit and even though there maybe considerable expansion and contraction of the air within the fixture it will not be suflicient to break the liquidseal. Furthermore, if the fixture becomes too heated the fins of the holder will radiate the heat thereby preventing expansion within the fixture.

I claim: V 1. A lighting fixture comprising a holder, a lamp supported therein, means ior sealing the lamp terminals in the holder, a globe with a circular well at the top into which the lower edge of the holder projects, and, a sealing liquid in' the well'into which the holder projects.

2. In a vapor-proof lighting fixture, a holder having a circular depending rib, a globe therefor having a circular sealing liquid containing well at the top into which the rib extends.

8. In a vapor proof lighting fixture, a holder having a depending rim, means forming a liquid holding container into which the rim projects, a lamp supported within the holder having sup- ;ply means extending below the rim and through a'sealing liquid in the container.

4. In a liquid seal vapor proof fixture, a holder having a depending rim, a globe having an upwardly extending liquid holding ring groove into which the rim projects, and the rim and groove having quick detachable connecting threads independent of the liquid seal between them when connected.

5. A lighting fixture comprising a holder, a lamp supported therein, a globe also supported by the holder and with it enclosing the lamp, separate means comprising a ring container with sealing liquid therein forminga liquid sealat the top and at the bottom of the holder to prevent the admission or discharge of gases to or from the interior of the fixture.

6. In a lighting fixture, a holder, a globe supported thereby, and a fluid sealing joint between the globe and holder comprising cooperating upright and depending ribs at the junctures of the globe and holder to form a liquid receiving groove in the lower part into which a'rib from the other part extends, and sealing liquid in the groove of a depth to partially cover the depending rib.

'2. In a lighting fixture, a holder, and a globe having cooperating rimportions to extend one within the other and threaded means for con-- necting the globe and holder independent of the liquid seal and providing a liquid receiving groove between the rim portions, and a sealing liquid in the groove between the rim portions to pre-'- vent the passage of gas or dirt therethrough.

8. In a lighting fixture, a supporting holder having a conductor opening, a lamp within the holder having conductors extending through the opening and a liquid seal for the opening comprising a rib surrounding the opening and de- 

